1. Field of the Invention
The illustrative embodiments relate generally to an improved system for illumination for vehicles, and more particularly, to a method and apparatus for adjusting the angle of spread of light from a narrow angle spot light to a wide angle flood light embedded into a single lighting system for vehicles, especially vehicles designed for purposes of unsteady and uneven terrain, such as, without limitation, off-road vehicles and sport utility vehicles.
2. Background Art
In any off-road vehicle, the characteristics of illumination as produced by the lighting systems assembled with the vehicle are of critical importance to the driver. In off-road vehicles, lighting systems are frequently utilized in nighttime driving, and frequently travel over rough and uneven terrain or surfaces.
In the off-road vehicle industry, a light stick is the term commonly used for an enclosed lighting unit, which is frequently combined with a light source such as a set of light emitting diodes (hereinafter referred to as LED or LEDs). Such LED lights are oftentimes enclosed in a single housing unit, whereby the lighting unit may be programmed to provide additional lighting for aiding a driver and may be mounted or fixed to the vehicle.
Typically, the angle of spread is fixed for a single light stick, meaning that the light produced by the set of LEDs is emitted at a defined, non-variable angle of spread. Angle of spread refers to the beam angle that a beam of light as produced by the LED in conjunction with an optic or reflector can be measured or described. When measured, the beam angle is measured in degrees. A range of terms is also used to characterize or describe the light beam angle ranging from very narrow spot light to wide flood light.
A method to calculate the beam angle and more technical definition states that the beam angle is the angle between those points on opposite side of the light beam axis where the intensity of the light emitted drops to 50% of the maximum. The measurement is determined in terms of degrees. LED lighting like most lights come with a variety of descriptions for the size of the area illuminated by the light bulb. Examples include LED flood light, LED spot light, narrow beam LED light, and wide beam LED strip lights. Each is a way of stating LED beam angle. Typically a narrow beam angle is a ‘spot’ of light and a broader beam angle ‘floods’ an area with light, called a flood light. LED beam angles are not used consistently by light bulb manufacturers. Generally used terms for the angle of spread of light beams include, very narrow spot, narrow spot, spot, narrow flood, flood, wide flood, and very wide flood. Thus, the angle of spread of light emanating from a light source has a variety of angles at which the light beam may be set to function.
The different beam angles of spread serve different purposes. Light beams projected at narrow angle can function to illuminate at a further distance for an off road vehicle. In contrast to the narrow spot light, when a wide flood beam is utilized, the user seeks to illuminate a wider general area.
A significant limitation to the type of light beam available to a user is that presently available apparatuses only provide the ability to implement a fixed set of light spreads that is emitted from an auxiliary vehicle LED light stick or light bar. In other words, the light spread emitted is either a fixed set of narrow light beam or a wide light beam or combination. It would be desirable to provide the ability to have an adjustable light spread, so that the user may select the necessary light spread according to the surroundings and the optimal type of lighting required on the same auxiliary vehicle LED system.
Many of the currently available processes for installing auxiliary vehicle LED lights to a vehicle is often a labor intensive, expensive, time-consuming, and arduous process that may result in permanent modifications and alterations to the appearance and operating system of a motor vehicle. Thus, it is desirable that illumination options be maximized to reduce the labor and cost associated with such installation.